JPH0530530B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an embossing device for forming irregularities of an arbitrary pattern on a thin metal plate having a decorative coating made of a decorative coating or film. In general, thin metal sheets, particularly organic coated steel sheets, fluorine resin coated steel sheets, and vinyl chloride steel sheets, are being used for a wide variety of purposes. This is because this type of steel sheet has excellent workability and design, and is also durable. Recently, demand has shifted from the above-mentioned flat steel plates to steel plates with enhanced fashionability by adding a three-dimensional effect or two-tone color to the surface. As a steel plate corresponding to this, for example, a steel plate on which an irregular pattern is formed by embossing is commercially available. However, when a salt water spray no test (JIS-Z-2371) was conducted on these steel plates, it was found that 500 to 1000
Rust and peeling of the paint film were observed on the bent parts over time. In addition, when observing the surface of this type of steel plate under 30x magnification, it can be seen that some of the membranes at the bends of concave and convex parts are peeled off and wrinkled, scratched, cracked, or thinned. , cracks were occurring. Furthermore, when embossing was done, the harsh process caused severe residual distortion, and oil cans appeared on the decorative surface, detracting from its aesthetic appearance. In order to eliminate these drawbacks, the present invention does not apply unreasonable tension during embossing, allows smooth transfer, softens the decorative film during embossing, and heats the steel sheet to achieve the allowable ductility. Furthermore, we have developed a thin metal sheet with an uneven patterned surface that facilitates correction of residual distortion during embossing, does not damage the coating film, and has a three-dimensional effect, durability, and formability. This paper proposes an embossing device that can form DESCRIPTION OF THE PREFERRED EMBODIMENTS An embossing device according to the present invention will be described in detail below using the drawings. FIG. 1 is a schematic configuration diagram showing an example of the above-mentioned device, in which 1 is a thin metal plate feeding section (hereinafter simply referred to as the feeding section), and an uncoiler 2 is shown.
and a pinch roller 3, and a flat metal thin plate (having a decorative coating such as a decorative coating or a decorative film) A wound into a coil is attached and constantly and effortlessly fed to the loop portion 4. It is for the purpose of The loop section 4 controls the speed difference and deviation that occur when transferring the thin metal plate A (hereinafter simply referred to as a coil) after the heater section 5 in the next process by loosening the coil A, and also This functions to prevent a large impact from being applied to the coil A being fed. In addition, the heater section 5
consists of a pinch roller 6 that also serves as a guide and a heater 7, and the pinch roller 6 has upper and lower rollers 6a and 6b.
The coil A is held between the rollers only at the time of line star, and thereafter the coil is fed to the heater 7 as a mere guide roller. Also, the heater 7 has a coil A
The cosmetic coating, which is essentially the coil A itself, is about 30 ~
The decorative film is heated to 60°C to soften it and prevent the decorative film from peeling off from the steel plate or cracking during embossing.
This prevents scratches and cracks from occurring. The heating methods include hot air method, direct fire method,
Either the hot wire method. The embossing roll 8 has a pattern consisting of male and female uneven parts formed on its outer circumferential surface. Upper and lower rolls 8a and 8b are engaged to form a coil A.
The upper and lower rolls 8
The gaps a and 8b are determined by the height of the uneven portion and the thickness of the coil A. 9 is used to correct the residual strain existing in the embossed coil A with a leveler, and as shown in Fig. 2, upper rollers 9a ₁ , 9a ₂ , 9a ₃ , ... 9an (up to 9a ₃ are shown in the figure) , lower rollers 9b ₁ , 9b ₂ , 9b ₃ , 9b ₄ ,...9bn
(9b to ₄ are shown in the figure) in a zigzag pattern, and the gap G between the upper roller group 9a and the lower roller group 9b can be adjusted.
No. 10 is heated 50 to 100 degrees from the back side of thin metal plate A to remove residual strain without damaging the coating film.
It is heated at ℃. As a heating method, for example, in addition to the above-mentioned heating method, laser beam irradiation is performed so as to average the temperature or to form a temperature gradient. Moreover, the heating temperature is configured so that the temperature increases not only in the traveling direction but also in the width direction from the center to both sides. Of course, it is preferable that the cover 10a covers the entire leveler 9, with only the entrance and exit of the thin metal plate A being an opening.
11 is a tensioning pinch roller and embossing roll 8
The rotation speed is set to be faster than that of the coil A, and the coil A is passed through the steps of the embossing roll 8 and the leveler 9 with the coil A in tension (under tension). Next, the operation of the embossing device according to the present invention will be explained. First, the coil A attached to the feeding section 1 is fed to the loop section 4 via the pinch roller 3. In addition, at this time, the coil A is connected to the pinch roller 3.
Since the uncoiler 2 is equipped with a braking device (not shown) even when the coil A is pulled by the uncoiler 2, the coil A is fed to the loop section 4 under a certain permissible tension. The coil A is then transferred from the loop section 4 to the heater section 5 by a pinch roller 6 which also serves as a guide.
The cosmetic film is then fed to a heater 7, where it is heated to about 30 to 60°C to soften the decorative film, and then fed to an embossing roll 8. Note that the pinch roller 6 that also serves as a guide passes the coil A through the heater section 5 to the embossing roll 8.
It functions as a pinch roller until it is guided, and thereafter it functions as a mere guide roller. Next, the coil A sent out from the heater section 5 is passed through an embossing roll 8, which continuously forms an embossed pattern on the coil A consisting of concave portions B and convex portions C as shown in FIG. 3, for example. It is. At this time, although no special tension is applied to the coil A, there is a force relationship in which a tension that does not loosen is exerted on the loop part 4 of the coil A by its own weight and the tension of the embossing roll 8. is one to which almost no tension is applied. Immediately after being embossed with the embossing roll 8, the coil A is stretched by the tensioning pinch roller 11, and while passing through the heating machine 10, about
It is heated to 50 to 100°C, and the leveler 9 smoothly corrects the residual strain, flattens the entire coil A without crushing the uneven parts B and C, and then sends it to the next process. be. In addition, since leveler 9 is in a state where tension is added in one direction,
It can be easily flattened and residual strain can be easily released by the heating. Of course, the tension within the above range is within the range of force that does not change the embossed pattern. Next, a test piece embossed using the above-mentioned apparatus will be compared with a test piece embossed using a conventionally used apparatus. Coil A is a colored galvanized iron plate (thickness: 0.27 mm) according to JIS-G-3312, and heater 7 is used.
The temperature was varied from 10 to 80°C, the embossing depth was 0.9 mm, the ratio of concave part B to convex part C was 1:1, and the embossing speed was 30 m/min.
And so. Note that the coating for coil A is an alkyd resin-based paint. Then, when the temperature of the surface of the coil A, the so-called temperature of the decorative film (in this case, the paint film) is changed from 10 to 80°C, the decorative film peels off, cracks, cracks, and shrinks. , the state of the wound is the fourth
This is shown as a line graph in the figure. Further, the flatness and degree of residual strain (pekotsuki) of the coil A sent out from the leveler 9 were visually observed. In addition,
The inspection methods include (1) the apparent number of Pekotsuki present per meter of coil A, (2) the distribution of Pekotsuki, and (3) the height difference of Pekotsuki (bottoms and tops of the designed uneven parts). (difference between the surface and the actual bottom and top surfaces), and (4) observations about the overall appearance.

[Table] Furthermore, the results of a salt water spray test (1500 hours) of the coils formed in the example (coil A when the decorative coating was heated to 50°C) and the comparative example were as shown in the table below.

[Table] What has been described above is only one embodiment of the embossing method according to the present invention, and the temperature from the heater 7 to the tensioning pinch roller 11 is kept within about 30 to 60°C, and the uneven portion B, Depending on the distribution ratio of C, the height difference of the leveler rollers can be increased or the distribution can be arranged so as to spread out from the center. As described above, according to the embossing device according to the present invention, only vertical force acts on the coil during embossing, and almost no tension acts on the coil, so the embossed pattern does not shift during processing and a beautiful uneven shape is created. Can form patterns. By heating the decorative film and making it soft enough for embossing,
The decorative film does not peel off from the steel plate during embossing, or the decorative film wrinkles, cracks, scratches, or cracks, resulting in a beautiful decorative film with weather resistance, scratch resistance, and chemical resistance. It can form an excellent cosmetic film. The residual strain formed by embossing will be reduced in a heated environment.
In addition, by flattening with a leveler under tension, residual strain can be easily and sufficiently removed, and a concave-convex pattern with no unevenness and full of three-dimensional effect can be formed. Along with arranging the lines in a straight line,
Since the number of places where the coil is held is reduced and the flow is made such that no unreasonable force is applied, the coil flows smoothly and embossing can be easily performed. The decorative coating on the coil is heated and embossed before it cools down, so it is not affected by the working environment. Embossing can be done at high speed because it uses a straight line and has fewer steps. It has the following characteristics.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing an example of an embossing device according to the present invention, FIG. 2 is a perspective view partially showing a leveler that is a part of the embossing device, FIG. 3 is a perspective view showing an example of an embossed pattern, and FIG. FIG. 4 is a characteristic diagram showing the temperature of the decorative film and the occurrence of cracks, etc. 1... Metal thin plate delivery section, 5... Heater section, 8...
... Emboss roll, 9 ... Leveler, 10 ... Heating machine, 11 ... Pinch roller for tension, A ... Metal thin plate.

Claims (1)

[Claims] 1. In an apparatus for embossing a coiled thin metal plate having a decorative coating, there is a thin metal plate feeding unit consisting of an uncoiler and a pinch roller for feeding the thin metal plate, and a thin metal plate fed from the feeding unit to loosen the thin metal plate. A loop part that stores the metal sheet in an open state and adjusts the process before and after the process, a heater part that heats the thin metal sheet to 30 to 60℃, and an emboss that creates a desired uneven pattern on the thin metal sheet sent out from the heater part. A roll, a leveler placed after the roll, a heating machine that heats the thin metal plate at 50 to 100°C from the back side of the leveler, and a tension pinch roller placed at the outlet of the leveler are arranged in a straight line. Further, an embossing device characterized in that the embossing roll and the tensioning pinch roller are in a tension state.